1. Field of Invention
The present invention relates to electrical pulse power systems integrated with low timing jitter switching, transformation lines and impedance matched antenna to generate an intense electromagnetic pulse train. EMP denotes electromagnetic pulse.
2. Description of Prior Art
U.S. Pat. No. 7,830,040 (Coiled transmission line pulse generators) describes a method and apparatus disclosure for fabricating and constructing solid dielectric “Coiled Transmission Line” pulse generators in radial or axial coiled geometries. The pour and cure fabrication process enables a wide variety of geometries and form factors. The volume between the conductors is filled with liquid blends of monomers, polymers, oligomers, and/or cross linkers and dielectric powders; and then cured to form a high field strength and high dielectric constant solid dielectric transmission lines that intrinsically produce ideal rectangular high voltage pulses when charged and switched into matched impedance loads. Voltage levels may be increased by Marx and/or Blumlein principles incorporating spark gap or, preferentially, solid state switches, such as optically triggered thyristors, which produce reliable, high repetition rate operation. Moreover, these Marxed pulse generators can be DC charged and do not require additional pulse forming circuitry, pulse forming lines, transformers or a high voltage spark gap output switch. The apparatus accommodates a wide range of voltages, impedances, pulse durations, pulse repetition rates, and duty cycles. The resultant mobile or flight platform friendly cylindrical geometric configuration is much more compact, light weight, and robust than conventional linear geometries, or pulse generators constructed from conventional components. Installing additional circuitry may accommodate optional pulse shape improvements. The Coiled Transmission Lines can also be connected in parallel to decrease the impedance, or in series to increase the pulse length.
This approach is deficient in that it is principally a delta function/soliton like pulse event device. As noted in the closing paragraphs of this sub-section, these typically result in essentially broadband pulsed radiation emission, not a harmonic train and thus they cannot effectively or easily be directed.
U.S. Pat. No. 7,071,631 (Electromagnetic pulse device) describes an electromagnetic pulse device disclosure wherein a conductive coil, and optionally a conductive core disposed within the coil and spaced apart there from. One or more plasma discharge devices are disposed at least partially along a length of the conductive coil and are spaced apart from the conductive coil. A spark gap or similar device is attached to the plasma discharge devices to activate them to produce a traveling electrical discharge. The discharge creates a traveling short circuit in the conductive coil thereby compressing the magnetic field. The result is the production of an electromagnetic pulse. Further disclosed is a method for producing an electromagnetic pulse.
This approach is deficient in that it is principally a delta function/soliton like pulse event device. As noted in the closing paragraphs of this sub-section, these typically result in essentially broadband pulsed radiation emission, not a harmonic train and thus they cannot effectively or easily be directed.
U.S. Pat. No. 4,845,378 (EMP generator) describes a generator concept disclosure by means of which, in particular, the effects of so called nuclear electromagnetic pulses on electrical or electronic devices can be simulated by applying the so called current injection technique. In the context of the generator concept according to the invention, in particular, a pneumatically controllable very fast spark gap is disclosed. Furthermore, a generator circuit having two spark gaps is disclosed which is capable of generating a voltage pulse having an amplitude which is four times as large as the voltage of its voltage supply. With the exception of spark gaps, the components of the generator circuit only need to be designed for the above voltage of the voltage supply with respect to their continuous loading. The generator circuit according to the invention, in particular in conjunction with the spark gap according to the invention allows a very fast efficient pulse generator to be constructed.
This approach is deficient in that it is principally no more than a simulator.
U.S. Pat. No. 6,477,932 (Explosive triggered RF beam source) describes an explosive triggered RF beam source disclosure constructed solely from a pulse generation device, whose generated pulses are radiated directly at a target. The pulse generator is a magnetic flux compressor, and has a coil that is filled with explosive material. A capacitive load (C sub L) integrated into the RF beam source is connected on the output side to the pulse generator, and forms an electrical resonating circuit with the coil and simultaneously functions as an antenna. Preferably an element is mounted in the region between the coil body and the windings to increase the number of free electrons for supporting the plasma formation and attaining a higher conversion of chemical energy into electrical energy, and therefore inducing a higher frequency
This approach is deficient for several reasons. Firstly, it is limited to a one-off, single use event. Secondly, since such single event use is associated with detonation, it can never be integrated into any kind of personnel operated vehicle or system. Thirdly, since it is explosively driven, phase up of multiple units in a confined area is just not practical, even if explosive triggering and system response reproducibility was such as to render it feasible.
There are a number of options which have been focused on over several decades or more. These include very short duration event devices, typically nanosecond or less delta function or appearance wise soliton like events. These produce broadband radiation of bandwidth essentially inversely proportional to soliton/delta function pulse duration and often best fit within the sub-hyperband to hyperband functional definition.
Sources have included explosively driven flux compressors, frozen wave generators, transmission line pulsars and various forms of pulsed transformers, Marx bank arrangements and their analogues driving suitable antenna. The frozen wave generators and transmission line pulsars can produce a pulse train, but the pulse train concerned is typically deficient in that it is not definitively harmonic in character. The frozen wave generator requires multiple switches which have to be closed with minimal temporal jitter and well defined delay, and the transmission line pulsar generates a pulse train only into an impedance mismatch with load typically greater than line. If switched into an impedance matched load, the output is a unitary near ideal square pulse.
The alternative has largely been to generate pulse trains of limited bandwidth but high power from various microwave devices including Backward Wave Oscillators (BWO), Virtual Cathode Oscillators (Vircator's) and other high power radio frequency sources.
As a possible example of the forgoing, or related systems, the SBIR solicitation A10-045 (June 2010) is revealing. It is stated under description “For example, a unitary 100 kW class solid state system (specific operational details are not publishable in open forum) recently designed to engage targets at ranges of less than 100 meters required a 6 meter cargo container, a dedicated generator, extensive heat exchanger system and antenna system greater than two cubic meters.” From an operational, practical and almost any other vantage, including certainly cost point of view, this is clearly deficient and borders on the absurd.
In the case of the soliton like/delta function methodology the approach is deficient in that achievement of any kind of truly useful system effective range is not practical given the system bandwidth, as the native divergence off any sending aperture is a function of the frequency components involved and thus control, or localization of the transmitted field at any significant range requires large to very large and impractical transmitting apertures. In addition, achievement of meaningful phase correlation, specifically phase up between several similar soliton like sources, for events shorter than some fraction of a nanosecond, is very challenging other than if switching is initiated by plasma channels formed by an ultra short pulse (USP) laser event interacting via resonance enhanced multi-photon ionization (REMPI) with a suitable gas.
In the case of the microwave, pulse train devices, high power has been generated, but these are typically deficient in the sense that this has been from significantly sophisticated systems requiring intense relativistic electron beams. In addition, the switched, high voltage supplies required to drive these electron beams and, quite often, vacuum systems integral with these devices, as intense electron beam creation and stopping is associated with plasma emission and thus contamination of its necessary vacuum environment, are associated with significant issues including system volume, logistics and simple reliability/survivability. These devices, in addition, typically function at centimetric or shorter wavelengths typically at frequencies in excess of 30 GHz. Atmospheric attenuation of these wavelengths can be significant under anything other than good weather conditions, which is another practical deficiency.